Annotation of src/usr.bin/passwd/local_passwd.c, Revision 1.60
1.60 ! robert 1: /* $OpenBSD: local_passwd.c,v 1.59 2021/07/12 15:09:20 beck Exp $ */
1.3 deraadt 2:
1.1 deraadt 3: /*-
4: * Copyright (c) 1990 The Regents of the University of California.
5: * All rights reserved.
6: *
7: * Redistribution and use in source and binary forms, with or without
8: * modification, are permitted provided that the following conditions
9: * are met:
10: * 1. Redistributions of source code must retain the above copyright
11: * notice, this list of conditions and the following disclaimer.
12: * 2. Redistributions in binary form must reproduce the above copyright
13: * notice, this list of conditions and the following disclaimer in the
14: * documentation and/or other materials provided with the distribution.
1.29 millert 15: * 3. Neither the name of the University nor the names of its contributors
1.1 deraadt 16: * may be used to endorse or promote products derived from this software
17: * without specific prior written permission.
18: *
19: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29: * SUCH DAMAGE.
30: */
31:
32: #include <sys/types.h>
1.2 deraadt 33: #include <sys/stat.h>
1.21 millert 34: #include <sys/uio.h>
35:
1.7 weingart 36: #include <err.h>
1.1 deraadt 37: #include <errno.h>
1.21 millert 38: #include <fcntl.h>
1.54 mestre 39: #include <paths.h>
1.21 millert 40: #include <pwd.h>
1.1 deraadt 41: #include <stdio.h>
1.28 deraadt 42: #include <stdlib.h>
1.21 millert 43: #include <signal.h>
1.1 deraadt 44: #include <string.h>
1.2 deraadt 45: #include <unistd.h>
46: #include <util.h>
1.14 millert 47: #include <login_cap.h>
1.50 tedu 48: #include <readpassphrase.h>
1.1 deraadt 49:
1.49 tedu 50: #define UNCHANGED_MSG "Password unchanged."
1.27 millert 51:
1.7 weingart 52: static uid_t uid;
1.33 millert 53: extern int pwd_check(login_cap_t *, char *);
54: extern int pwd_gettries(login_cap_t *);
1.14 millert 55:
1.39 djm 56: int local_passwd(char *, int);
1.25 millert 57: char *getnewpasswd(struct passwd *, login_cap_t *, int);
58: void kbintr(int);
1.1 deraadt 59:
1.7 weingart 60: int
1.26 deraadt 61: local_passwd(char *uname, int authenticated)
1.1 deraadt 62: {
1.32 millert 63: struct passwd *pw, *opw;
1.14 millert 64: login_cap_t *lc;
1.15 millert 65: sigset_t fullset;
66: time_t period;
1.21 millert 67: int i, pfd, tfd = -1;
1.20 millert 68: int pwflags = _PASSWORD_OMITV7;
1.1 deraadt 69:
1.47 tim 70: if (!(pw = getpwnam_shadow(uname))) {
1.7 weingart 71: warnx("unknown user %s.", uname);
1.1 deraadt 72: return(1);
73: }
1.46 deraadt 74:
1.57 semarie 75: if (unveil(_PATH_MASTERPASSWD_LOCK, "rwc") == -1)
1.59 beck 76: err(1, "unveil %s", _PATH_MASTERPASSWD_LOCK);
1.54 mestre 77: if (unveil(_PATH_MASTERPASSWD, "r") == -1)
1.59 beck 78: err(1, "unveil %s", _PATH_MASTERPASSWD);
1.55 mestre 79: if (unveil(_PATH_LOGIN_CONF, "r") == -1)
1.59 beck 80: err(1, "unveil %s", _PATH_LOGIN_CONF);
1.57 semarie 81: if (unveil(_PATH_LOGIN_CONF ".db", "r") == -1)
1.59 beck 82: err(1, "unveil %s.db", _PATH_LOGIN_CONF);
1.54 mestre 83: if (unveil(_PATH_BSHELL, "x") == -1)
1.59 beck 84: err(1, "unveil %s", _PATH_BSHELL);
1.58 anton 85: if (unveil(_PATH_SHELLS, "r") == -1)
1.59 beck 86: err(1, "unveil %s", _PATH_SHELLS);
1.54 mestre 87: if (unveil(_PATH_PWD_MKDB, "x") == -1)
1.59 beck 88: err(1, "unveil %s", _PATH_PWD_MKDB);
1.46 deraadt 89: if (pledge("stdio rpath wpath cpath getpw tty id proc exec", NULL) == -1)
90: err(1, "pledge");
91:
1.32 millert 92: if ((opw = pw_dup(pw)) == NULL) {
93: warn(NULL);
94: return(1);
95: }
1.14 millert 96: if ((lc = login_getclass(pw->pw_class)) == NULL) {
97: warnx("unable to get login class for user %s.", uname);
1.36 moritz 98: free(opw);
1.14 millert 99: return(1);
100: }
1.1 deraadt 101:
1.13 millert 102: uid = authenticated ? pw->pw_uid : getuid();
1.1 deraadt 103: if (uid && uid != pw->pw_uid) {
1.8 millert 104: warnx("login/uid mismatch, username argument required.");
1.36 moritz 105: free(opw);
1.1 deraadt 106: return(1);
107: }
108:
1.14 millert 109: /* Get the new password. */
110: pw->pw_passwd = getnewpasswd(pw, lc, authenticated);
111:
1.46 deraadt 112: if (pledge("stdio rpath wpath cpath getpw id proc exec", NULL) == -1)
113: err(1, "pledge");
114:
1.14 millert 115: /* Reset password change time based on login.conf. */
1.48 guenther 116: period = (time_t)login_getcaptime(lc, "passwordtime", 0, 0);
1.19 millert 117: if (period > 0) {
1.14 millert 118: pw->pw_change = time(NULL) + period;
1.19 millert 119: } else {
120: /*
121: * If the pw change time is the same we only need
122: * to update the spwd.db file.
123: */
124: if (pw->pw_change != 0)
125: pw->pw_change = 0;
126: else
1.20 millert 127: pwflags = _PASSWORD_SECUREONLY;
1.19 millert 128: }
1.14 millert 129:
1.15 millert 130: /* Drop user's real uid and block all signals to avoid a DoS. */
131: setuid(0);
132: sigfillset(&fullset);
133: sigdelset(&fullset, SIGINT);
134: sigprocmask(SIG_BLOCK, &fullset, NULL);
135:
1.46 deraadt 136: if (pledge("stdio rpath wpath cpath proc exec", NULL) == -1)
137: err(1, "pledge");
138:
1.15 millert 139: /* Get a lock on the passwd file and open it. */
140: pw_init();
1.21 millert 141: for (i = 1; (tfd = pw_lock(0)) == -1; i++) {
142: if (i == 4)
1.38 jsing 143: (void)fputs("Attempting to lock password file, "
1.21 millert 144: "please wait or press ^C to abort", stderr);
145: (void)signal(SIGINT, kbintr);
146: if (i % 16 == 0)
1.15 millert 147: fputc('.', stderr);
1.21 millert 148: usleep(250000);
1.15 millert 149: (void)signal(SIGINT, SIG_IGN);
150: }
1.21 millert 151: if (i >= 4)
152: fputc('\n', stderr);
1.41 guenther 153: pfd = open(_PATH_MASTERPASSWD, O_RDONLY | O_CLOEXEC, 0);
1.56 deraadt 154: if (pfd == -1)
1.15 millert 155: pw_error(_PATH_MASTERPASSWD, 1, 1);
156:
1.18 millert 157: /* Update master.passwd file and rebuild spwd.db. */
1.32 millert 158: pw_copy(pfd, tfd, pw, opw);
159: free(opw);
1.56 deraadt 160: if (pw_mkdb(uname, pwflags) == -1)
1.19 millert 161: pw_error(NULL, 0, 1);
1.14 millert 162:
1.1 deraadt 163: return(0);
164: }
165:
166: char *
1.26 deraadt 167: getnewpasswd(struct passwd *pw, login_cap_t *lc, int authenticated)
1.1 deraadt 168: {
1.43 tedu 169: static char hash[_PASSWORD_LEN];
1.52 tedu 170: char newpass[1024];
1.44 tedu 171: char *p, *pref;
1.11 provos 172: int tries, pwd_tries;
1.24 millert 173: sig_t saveint, savequit;
1.1 deraadt 174:
1.24 millert 175: saveint = signal(SIGINT, kbintr);
176: savequit = signal(SIGQUIT, kbintr);
1.23 millert 177:
1.13 millert 178: if (!authenticated) {
1.60 ! robert 179: fprintf(stderr, "Changing password for %s.\n", pw->pw_name);
1.27 millert 180: if (uid != 0 && pw->pw_passwd[0] != '\0') {
1.52 tedu 181: char oldpass[1024];
1.50 tedu 182:
183: p = readpassphrase("Old password:", oldpass,
184: sizeof(oldpass), RPP_ECHO_OFF);
1.31 millert 185: if (p == NULL || *p == '\0') {
1.60 ! robert 186: fprintf(stderr, "%s\n", UNCHANGED_MSG);
1.27 millert 187: pw_abort();
1.31 millert 188: exit(p == NULL ? 1 : 0);
1.27 millert 189: }
1.42 tedu 190: if (crypt_checkpass(p, pw->pw_passwd) != 0) {
1.27 millert 191: errno = EACCES;
1.51 gsoares 192: explicit_bzero(oldpass, sizeof(oldpass));
1.27 millert 193: pw_error(NULL, 1, 1);
194: }
1.51 gsoares 195: explicit_bzero(oldpass, sizeof(oldpass));
1.13 millert 196: }
1.1 deraadt 197: }
1.26 deraadt 198:
1.33 millert 199: pwd_tries = pwd_gettries(lc);
1.1 deraadt 200:
1.50 tedu 201: for (newpass[0] = '\0', tries = 0;;) {
1.52 tedu 202: char repeat[1024];
1.50 tedu 203:
204: p = readpassphrase("New password:", newpass, sizeof(newpass),
205: RPP_ECHO_OFF);
1.31 millert 206: if (p == NULL || *p == '\0') {
1.60 ! robert 207: fprintf(stderr, "%s\n", UNCHANGED_MSG);
1.27 millert 208: pw_abort();
1.31 millert 209: exit(p == NULL ? 1 : 0);
1.9 deraadt 210: }
211: if (strcmp(p, "s/key") == 0) {
1.60 ! robert 212: fprintf(stderr, "That password collides with a system feature. Choose another.\n");
1.9 deraadt 213: continue;
1.1 deraadt 214: }
1.26 deraadt 215:
1.37 deraadt 216: if ((tries++ < pwd_tries || pwd_tries == 0) &&
217: pwd_check(lc, p) == 0)
1.1 deraadt 218: continue;
1.50 tedu 219: p = readpassphrase("Retype new password:", repeat, sizeof(repeat),
220: RPP_ECHO_OFF);
1.53 millert 221: if (p != NULL && strcmp(newpass, p) == 0) {
222: explicit_bzero(repeat, sizeof(repeat));
1.1 deraadt 223: break;
1.53 millert 224: }
1.60 ! robert 225: fprintf(stderr, "Mismatch; try again, EOF to quit.\n");
1.53 millert 226: explicit_bzero(repeat, sizeof(repeat));
1.51 gsoares 227: explicit_bzero(newpass, sizeof(newpass));
1.1 deraadt 228: }
1.43 tedu 229:
1.24 millert 230: (void)signal(SIGINT, saveint);
231: (void)signal(SIGQUIT, savequit);
1.23 millert 232:
1.44 tedu 233: pref = login_getcapstr(lc, "localcipher", NULL, NULL);
1.50 tedu 234: if (crypt_newhash(newpass, pref, hash, sizeof(hash)) != 0) {
1.60 ! robert 235: fprintf(stderr, "Couldn't generate hash.\n");
1.51 gsoares 236: explicit_bzero(newpass, sizeof(newpass));
1.43 tedu 237: pw_error(NULL, 0, 0);
238: }
1.51 gsoares 239: explicit_bzero(newpass, sizeof(newpass));
1.44 tedu 240: free(pref);
1.43 tedu 241: return hash;
1.15 millert 242: }
243:
244: void
1.26 deraadt 245: kbintr(int signo)
1.15 millert 246: {
1.49 tedu 247: dprintf(STDOUT_FILENO, "\n%s\n", UNCHANGED_MSG);
1.27 millert 248: _exit(0);
1.1 deraadt 249: }